Operations, such as geophysical surveying, drilling, logging, well completion, and production, are typically performed to locate and gather valuable downhole fluids. Surveys are often performed using acquisition methodologies, such as seismic mapping, resistivity mapping, etc. to generate images of underground formations. These formations are often analyzed to determine the presence of subterranean assets, such as valuable fluids or minerals, or to determine if the formations have characteristics suitable for storing fluids. Although the subterranean assets are not limited to hydrocarbons such as oil, throughout this document, the terms “oilfield” and “oilfield operation” may be used interchangeably with the terms “field” and “field operation” to refer to a site where any types of valuable fluids or minerals can be found and the activities required for extracting them. The terms may also refer to sites where substances are deposited or stored by injecting them into the surface using boreholes and the operations associated with this process. Further, the term “field operation” refers to a field operation associated with a field, including activities related to field planning, wellbore drilling, wellbore completion, and/or production using the wellbore.
The term “dip” refers to a characteristic (or a measurement thereof) of a geological structure, such as a bed, fracture, fault, etc. in a subterranean formation or surface exposure. In particular, dip magnitude represents an angle between the geological structure (i.e., geological surface) and an imaginary horizontal plane while dip azimuth represents a direction of the dipping geological structure. One way to determine dips of subterranean formation is from dipmeter/borehole image data. For example, U.S. Pat. No. 7,640,111 B2 and P. Cheung et al., “Field Test Results of a New Oil-base Mud Formation Imager Tool,” SPWLA 42nd Annual Logging Symposium, Jun. 17-20, 2001 describe Oil Based Mud Imaging (OBMI) techniques for obtaining borehole images, which are then used to determine dips. Borehole imaging tool may also include density imaging tool, acoustic imaging tool, gamma-ray imaging tool, photo-electric factor imaging tool, etc. that generates various types of borehole images. In addition, example techniques for determining formation dip are described in U.S. Patent Publication No. 2004/0136267 A1; P. Wu et al., “Determining Formation Dip from a Fully Triaxial Induction Tool,” SPWLA 51st Annual Logging Symposium, Jun. 19-23, 2010; and Hanming Wang et al., “Determining Anisotropic Formation Resistivity at Any Relative Dip using a Multiarray Tiaxial Induction Tool,” SPE 103113, 2006 SPE Annual Technical Conference and Exhibition, Sep. 24-27, 2006. The triaxial induction resistivity tool is also known to those skilled in the art as the 3D resistivity tool.